Modelling Hybrid Lithium-ion & Lead-acid storage

New trend used in off-grid sector is to use Hybrid li-ion + lead acid storage like the solution provide with the Company BOS AG in Germany. Both batteries are used for supplying the load using a BMS for the li-ion which take care of the charge control of both battreis. The solution is very economical, and represents a potential solution for off-grid market.

How can we model such li-ion + lead acid in Homer and compare it to PURE li-ion storage scenario?